I decided to make the eccentric as one part because I wasn't sure how to pin the two together accuractly.

First, face the ends square.

Then carefully drill and ream two .125 holes that are the centers of the eccentrics.

Here is the layout for 1" eccentrics with 3/32 throw, 112 apart.

In the 4-jaw chuck, indicate one true.

You can rough down to 1.320" for the full length of the part.

Now turn the 1.000" diameter of the first eccentric.

With a 1/16" wide parting tool, put in the groove.

Test fit the eccentric strap before moving on.

Now indicate the other hole true.

With a square parting tool, turn the 1.000" diamter of the rear eccentric.

Use the 1/16" parting tool to groove the rear eccentric.
Test fit the eccentric strap before moving on.

Back in the 3-jaw chuck, turn the flange and drill and ream the shaft hole and part off.